This is pollen of Vinca minor, the Lesser Periwinkle. The center of the flower was featured in one of my macro posts, not too long ago.
These grains are not only huge, they're very sticky. The content of an entire anther comes off as a single glob that has roughly the behavior of a ball of duct tape, sticky side out.
How to get the grains apart? discomorphella suggested a great approach here, but I was short on both ingredients and time. So as a quick-and-dirty expedient, I tried just putting a little drop of ethyl acetate on the glob. That worked like a charm! The glob just melted, the individual grains dispersed into the drop, and as the drop dried, the pollen mostly got pulled into a nice tidy monolayer on the surface of the slide. Of course the sticky stuff didn't go away, it just got temporarily dissolved. I believe you can still see some of it, now collected as little "bridges" between the grains.
20X NA 0.40 objective, dry and no cover glass, Canon SD700 IS through eyepiece with unknown zoom, 20-frame stack with Helicon Focus (R=20,S=4). The scale bar is from a stage micrometer shot immediately after the stack.
What you're seeing is the green channel only. This pollen is water-white. There was a significant amount of color to be found in the image, but it was all due to lens aberrations and prismatic effects that did not help understanding.
--Rik
I love those little things covered in butter but don't tell my doctor 
)